OBJECTIVE LIFE SCIENCE
GENETICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -X-linked recessive diseases most often occur in males. Males have only one X chromosome. A single recessive gene on that X chromosome will cause the disease.
Detailed explanation-2: -If a male who has an X linked condition has a son, his son will never inherit the changed gene on the X chromosome. This is because men always pass on their Y chromosome to their sons (if they passed on their X chromosome they would have a daughter).
Detailed explanation-3: -A male has an X chromosome from his mother and a Y chromosome from his father. Females may get the defective gene either from her mother’s defective X, or, if her father has the disorder, from her father. In either case, the girl will be a carrier and will probably pass the defect to her offspring.